1. Technical Field
The present invention relates to a novel optical compensation film capable of contributing to widening viewing angles of polarizing plates, and a polarizing plate and a liquid crystal display device, having the optical compensation film, improved in viewing angle characteristics.
2. Background Art
Transmission-type liquid crystal display device generally has a pair of polarizing plates, disposed so as to align their axes of polarization orthogonally to each other. The orthogonality is, however, lost with respect to incident light coming in oblique directions, even if two polarizing plates are stacked so that the axes of polarization are orthogonal to each other. This is a reason for leakage of light from the liquid crystal display device in the black state, when viewed in oblique directions. In order to provide a liquid crystal display device excellent in the viewing angle characteristics, it may therefore be necessary to solve viewing angle dependence of polarizing plates. Aiming at obtaining wide-viewing-angle polarizing plates, various proposals have conventionally been made on combination of a polarizer and a retardation layer which exhibits predetermined optical characteristics (see Japanese Laid-Open Patent Publication Nos. H4-305602 and 2001-350022, for example).